I was initially drawn to Netbeans because at the time the GUI editor was nicer.
Netbeans 6.8 is when it started getting really good. It is by far the better IDE for php which has nothing to do with Java. It is also a capable Groovy and Ruby editor especially for local windows development.
7 is fantastic. The reason why I lean to Indigo is because I use it at work.
I haven't really used Netbeans for Java development. But I have noticed that there are niggly issues when using for ruby or C/C++ development. Mostly, residing in the syntax highlighter. (though, a few have to deal with getting the compiler correctly setup.)
I still prefer Netbeans over eclipse, however. Eclipse just always feels slow to me.
3.7 Indigo has only been out a since the end of June but it feels a hell of a lot faster than the previous 3.6 Helios release.
Microchip has ported their mplab software to netbeans and calls it mplabx. They did this because the previous software was windows only and now it is cross platform. It hasn't been a pleasant change for me though. The software isn't as reliable as the previous version and seems to be slower and clunkier . I'm not sure if that is netbeans fault or just trouble in microchip making the switch. It gives you an idea though of the possibilities with netbeans.
http://www.microchip.com/en_US/family/mplabx/index.html